


The reason comes on the common tongue of your loving me

by mohawke



Category: Fire Emblem: Fuukasetsugetsu | Fire Emblem: Three Houses
Genre: ? - Freeform, Cunnilingus, Desk Sex, Dream Sex, Explicit Sexual Content, F/M, First Time, Kinda, Masturbation, One Shot, PWP, Plot What Plot/Porn Without Plot
Language: English
Status: Completed
Published: 2019-10-25
Updated: 2019-10-25
Packaged: 2021-01-03 07:29:43
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 2,526
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/21175697
Author URL: https://archiveofourown.org/users/mohawke/pseuds/mohawke
Summary: Post time skip pwp. It's literally just smut with a bit of fluff at the end. Yeah. Mandatory Hozier lyric, religion but sexy. Silver Snow route but it doesn't really matter in this context for the most part.Update: Y'all I forgot to put this in the summary because I spaced. The italics in the beginning part are the dream part. If that was confusing I apologize. I got nervous and uploaded and then peaced out because I hadn't written anything in so long and secretly thought everyone would hate it. So my bad!





	The reason comes on the common tongue of your loving me

**Author's Note:**

> Yeah so this is literally the first thing I've written since March of 2017, I haven't actually finished his romance yet that's a work in progress. If you like it let me know! I got hit hard by my thirst for Seteth and this was born.

_“We shouldn’t be doing this” he says huskily, fingers trailing down her bare skin. His lips capture hers in a heated kiss, tugging her lower lip between his teeth as he pulls back to look at him._

Byleth jolts awake, feeling entirely too warm as she takes in her surroundings. Moonlight steams into her room and she lets out a huff of frustration as she lies back down. It’s the same dream every time and it always ends far too early, leaving her annoyed and unfulfilled. 

Closing her eyes she replays the dream in her mind. The man before her is a tall and imposing figure. She tries to tell herself it’s someone else but she knows it’s him every time. Slowly she trails her fingers along her inner thigh, imagining his hands on her skin. 

_His lips are on hers, insistent and hungry sending her pulse racing. _Byleth lets out a breathy sigh, her hand reaching the juncture of her thighs. _She eagerly meets each kiss, fingers twining in his hair, that familiar shade of green striking against her skin. Her head falls back as he cups her breast in his hand, thumb brushing over her nipple. _

She slides her fingers along her folds, less than surprised to find herself slick with want. She circles her clit with her thumb, stifling a moan as she works towards her orgasm. Her other hand toys with her breast as she imagines him capturing the taut peak between his teeth. 

_His lips trail down her skin and every part of her feels aflame, the touch too much but not enough. She whimpers as he nips the insides of her thighs with his teeth, the warmth of his breath leaving her aching as he looks up at her. _

She arches into her touch sweat beading on her brow. She needs more, needs him. _His tongue parts her and she sees stars, his touch quickly undoing her._

She’s close her breathing heavy as she toys with herself. With one final touch she cries out, his name spilling from her lips _“Seteth…” _Byleth lies there, chest heaving as she catches her breath, dimly aware of the sweat slicked hair sticking to her neck. Sleep soon finds her and she wakes to sunlight pouring into her room and the sound of the monastery bell ringing. 

* * *

As she dresses herself she berates herself for letting her imagination get the best of her. She tries to quell the thoughts, forcing it out of her mind as she leaves her quarters. 

Byleth goes about her normal routine, avoiding his gaze each time she passes him. It’s foolish really, he isn’t aware of the thoughts racing through her mind she tries to tell herself. It was a momentary lapse, nothing to worry about. She could certainly move past it.

Throughout her time at Garreg Mach they’d slowly grown closer but she was rather certain the attraction was one-sided, some foolish girlish crush. She’d been a mercenary for the better part of her life yet he made her feel skittish, acutely aware of every movement she makes near him. As the day winds into night she finishes wandering the monastery intent on returning to her room. The second floor is mostly quiet at this hour, the other professors having left their offices for the night. As she nears his office she hears the shuffling of papers and she curses her luck. 

“Professor?” he calls out and she flushes, her intention of passing his office undetected quickly thwarted. As she moves to leave fingers grasp her wrist and she turns to face him, leaving her face in what she hopes is a reasonable mask of neutrality. 

“You’ve been avoiding me,” Seteth states matter of factly betraying no hint of emotion as she shakes her head, voice catching as she tries to refute his claim. “I haven’t, I’ve been...busy,” she manages to say, the words far from convincing.

“Oh? Well it seems you’re free at the moment. Come in, we have matters to discuss.” The commanding tone of his voice sends a flash of heat through her veins and she mentally chides herself for thinking back on her dream from the previous night. Idly she wonders if he’d have that same presence then. 

“Very well” she assents with a slight nod suddenly all too aware of his grip on her wrist. She gazes down pointedly and he clears his throat, relinquishing his hold as he ushers her into his office, closing the door behind them. 

He gestures towards the desk and she acquiesces, drawing closer to him to pore over the documents on his desk. Intel reports, supply requests, pleas for assistance–the usual matters in their efforts during the war that was currently ravaging Fódlan. She offers as much input as she can, keenly aware of his presence. She flushes when he accidentally brushes her hand with his, the same hands she had imagined on her last night. She immediately chides herself for the foolish thought. 

Once he’s satisfied that they’ve discussed everything she allows him to escort her towards the door. She swallows hard, his eyes catching hers as he reaches for the door. “Goodnight Professor” he says, gazing down at her. 

She parts her lips intent on replying but the words die on her tongue and she impulsively pulls him towards her, capturing his lips in an ill thought out kiss.She moves to leave, apologizing for her lapse in judgement but stops as he grabs her wrist, pulling her back to him as he places a heated kiss upon her lips. She whimpers softly as he deepens the kiss and she feels as though she should be embarrassed at the noise but she can’t bring herself to care. 

Pulling back Seteth looks at her, an unreadable expression on his face. “Byleth…” he says, voice husky as he murmurs her name. She can feel the blood thrumming in her veins and all trace of regret leaves her as he pulls her in for another kiss. “We shouldn’t be doing this,” he says but makes no move to stop. She moans as he captures her lips in another searing kiss, tugging her lower lip between his teeth. It’s not enough, she wants...no, she _needs _more. 

“Seteth,” she whimpers, allowing him to pull her closer. His long fingers twine in her hair as he gently tugs, angling her head back as he deepens the kiss, his tongue parting her lips. Her name falls from his lips and she closes her eyes, the longing tone sending sparks of pleasure down her spine. He guides her back towards his desk, only pausing to clear the papers from atop it. 

“Seteth…” Byleth pleads, meeting his gaze as he urges her onto the desk, settling between her legs as he draws her towards him for another kiss. He pulls back to look at her, eyes dark with hunger.

“We should stop, it isn’t right” he offers and she shakes her head, pulling him down for another long, desperate kiss. 

“Please,” she whispers and he acquiesces, his tongue slipping between her lips as he tilts her head. Every part of her aches for his touch. 

“Seteth,” she begs “touch me”. Any hint of reservation disappears, his hands gripping her waist as he pulls her flush to him. The feel of him hard against her thigh is positively sinful and she moans, the sound pulling a ragged groan from his lip, his breath warm against her neck. She sits up, removing her cape and top with shaking hands. She’s never needed anything more in her life. As he looks down at her in awe she flushes, hands instinctively moving to cover herself. 

He quickly grabs her wrists, looking down reverently at her. “Beautiful…” he murmurs, hands skating lightly down her arms. Byleth relaxes into his touch, seeking the warmth of his hands on her skin. The barely restrained look of hunger on his face makes her pulse thrum and she whimpers softly with want. Her fingers work on the buttons of his coat, itching to touch the skin that hides beneath. She eagerly runs her hands down the planes of his chest as he discards his shirt and coat unceremoniously behind him. She had always known he was strong, that much was evident in their training sessions or in battle but seeing him like this was enthralling.

He lets out a throaty moan as her hands inch lower and she can feel her skin flushing at the sound. She lets out a huff of impatience when he captures her hands in his. Relinquishing his hold his hands skate along her waist, coming up to cup her breasts, teasing her nipples to taut peaks. She arches into the touch, biting back a needy moan as he captures her lips in another heated kiss. 

Seteth groans as she brushes against him. It’s been a long time since he’d felt this way and it’s almost frightening to him how quickly she could awaken this reaction in him. His mind still tells him this is a bad idea but his resolve has quickly disappeared at the sight of Byleth beneath him, skin tinged pink with desire and need. Her breathy moans make his cock twitch and he has to close his eyes for a moment to regain some semblance of self control. 

Slowly he begins to lave hot open-mouthed kisses along her jawline, blazing a trail along the column of her neck. He bites down on the tender patch of skin near her shoulder, pulling a loud moan from the woman beneath him. He starts to apologize but she shakes her head, guiding him back down. His body thrums with desire, every sound she makes has him more undone. Restless hands find purchase in his hair as she writhes beneath him.

“Seteth please,” she begs and he lets out a low groan, capturing a rosy nipple between his teeth. She bites back a keening cry as he swirls his tongue against the hardened peak. 

His hands quickly find their way to her shorts, helping her ease out of them. He tosses them carelessly to the ground, quickly followed by her tights and shoes until she’s nearly bare beneath him. He can see the wet patch on her underwear and a strange sense of pride flows through him. He’s suddenly desperate to know what she tastes like, tugging them off before trailing his lips along her inner thighs. The heady scent of her is intoxication. He bites down on the sensitive skin, marking her with his teeth. She shudders beneath him as his breath ghosts over her folds, his eyes meeting hers as he parts her with his tongue.

Her eyes snap shut as he laves a long stroke along the wetness between her legs. 

“Watch” he says, barely recognizing his own voice through the hunger. She gazes down at him through half lidded eyes. It’s a captivating sight seeing her come undone beneath him. Her fingers find purchase in his hair, tugging almost to the point of pain as she desperately rocks her hips. It’s carnal and sinful and completely _right_. 

She lets out a throaty cry as he slowly thrusts his finger inside her, curling gently as he sucks her clit between his lips. She swears softly as he adds a second finger, feeling her adjust around the digits. 

“You look beautiful, spread out beneath me, desperate for my touch,” the words spill out unbidden, husky and low. She whimpers as he sucks on the aching bundle of nerves between her legs. 

“Don’t stop…” She says breathlessly and he complies, working her towards her peak. With one final thrust he feels her tighten around his fingers, thighs clenching around his ears as she lets out a long moan, his name tumbling from her lips. 

He waits for her breathing to slow before making his way back up her body, capturing her lips in a languid kiss. She sighs into it, the taste of herself on his tongue causing heat to pool in her belly. Straightening up his hands move to slide down his pants and he aches as she licks her lips. 

As he aligns himself with her entrance she grabs his wrist. 

“Wait I’ve never done this before” she confesses, averting her gaze.

“Do you want to stop?” He asks, pausing to read her expression. She shakes her head, meeting his gaze.

“Please, I need you,” Byleth begs and he swallows hard, mouth going dry at the words. Nodding he slowly thrusts his length inside her. She’s warm and wet and it takes every ounce of his self control to wait for her to adjust to him. Slowly he eases out, watching her face for any sign of discomfort as he eases back into her. Another slow thrust draws a sinful moan from her and he’s struck with a strange sense of pride that he’s the only one who has seen her like this. Slowly he begins to build up a rhythm, nipping at the tender skin beneath her ear. 

“More,” She pants, fingers curling around his bicep. The other hand is draped across the nape of his neck, fingers tangling in his hair as she desperately kisses him. 

He begins to quicken his pace and she arches into it, wanton moans filling his ears. With a hand on her hip he adjusts the angle of his thrusts, pulling a soft whimper from her lips. 

“Please Seteth,” she whines and he circles her clit with his thumb. He can tell she’s close and he knows he won’t last much longer with her tightening around him.

“Byleth,” he moans against her neck, fingers tangling in the familiar seafoam color of her hair. He nips at her earlobe and she cries out as she reaches her peak, walls fluttering around him as his name spills from her lips in a litany of cries. He follows shortly behind, one final thrust and he finishes, spilling inside her. 

She looks up at him as she tries to catch her breath, fingers gently toying with his hair. 

“Are you alright?” he asks once he’s regained his composure. Byleth nods, bringing him down for a slow, sweet kiss.

“You don’t regret it, do you?” She asks, studying his face.

“While the timing is perhaps ill-advised, no I don’t regret it” he says, brushing hair off her forehead. He’d been trying to bury his feelings for the enigmatic professor, telling himself that it wasn’t appropriate, that he needed to maintain a safe distance from her. He’d been slow to trust her but she’d proven herself to be a reliable ally and he owed her more than a debt of gratitude for Flayn’s safe return five years ago. Perhaps once the war was over and they’d rescued Rhea they could make a real go at this, uninhibited by the demands of their positions.

“Thank you,” Byleth says softly and he looks at her quizzically.

“What for?” He asks, surveying her face.

“Everything” she murmurs, gently running her fingers along his jaw.

Yes. Perhaps there was a place in his heart for her. 


End file.
